Francis j



(N0 Modal) P. J. GARMAN. PROCESS OF RBFINING'SULPHUROUS PETROLEUM.

No. 501,988.. Patent'd July 25, 1893. I

811114224 507 We 11 e2 5. Carinwn UNITED STATES PATENT OFFICE.

FRANCIS J. CARMAN, OF WASHINGTON, DISTRICT, OF CGLUMBIA.

PROCESS OF REFlNlNG SULPHUROUS PETROLEUM.

SPECIFICATION forming part of Letters Patent No. 501,988, dated July 25, 1893.

Application filed May 19, 1893. Serial No. 474.771. N specimens.)

To all whom it may concern:

Be it known that I, FRANCIS J. CARMAN, a citizen of the United States, at present residing in the city of \Vashington, District of Columbia, have invented a new and useful Process for the Refining of Sulphurous Petroleum, and of which the following is a specification.

Sulphurous petroleum is the term applied to that class of natural oils which contain appreciable quantities of sulphur and other deleterious impurities, whose presence imparts an offensive odor to the oil and its products, or which develop an odor during combustion, and incrust the lamp chimney with the products of combustion.

The methods hitherto in use for the desulphurizirig'6f 'iiii neral oils have been m any and various. One method consists in agitating the distillates with chemicals, generally plumbate of soda, whereby certain sulphur com- .pounds will yield their sulphur, with formation and precipitation of sulphide of lead, and the removal of the excess of plumbatc by a second agitation with fiowers of sulphur.

It has been found, that, inasmuch as the oils contain sulphur in some forms of combination which will not yield to the plumbate, the

sulphur is not wholly eliminated; traces of lead oxide also remain dissolved-in the oil, thereby impairing its burning qualities.

Another method is the distillation of the crude oil or of a distillate therefrom," with metallic oxides, which may retain the sulphur in combination or may cause it to pass off in the form of sulphurous acid gas, or both. The disadvantages of this process are:

. first, the necessity of agitating, the oxides in the 011; second, the labor and expense incidental to revivifying the spent oxides.

Another method consists in distilling the crude oil or its distillates, and removing the sulphur from the vapor before condensation; one method in this class, is to pass the vapor over a surface of solid metallic particles, or of metallic oxides,which are keptsuperheated In order to prevent condensation of the vapor undergoing treatment. The desulphurizing agent is afterward removed from its chamber and suitably roasted or otherwise renovated. 'lhe obgections to this method are: first, that it involves considerable handling and ma- .tacle.

through or over a mass of molten metalliced go of sulphurous oil refining, will show that any process of this nature,in order to be eminently cflicient and economical, must employ an agent of such nature and under such conditions that it will, first, so react upon the sulphur compoundsas toreducc them tothe same form of combination; second, which will at the same time readily combine with the sulphur while in that form of combination; third, which will not be hampered by an inert accumulation or crust of the resultant compound; fourth, which owiug't-o its nature and condition, is easily capable of being keptat the proper temperature with a small expenditure of fuel; fifth, which is capable of revivification with little or no loss of substance or of oil, with the least amount of labor, and also without being removed from its recep- The process of spraying the vapor lead, I find to answer each and all of these requirements.

My invention therefore consists, first, in passing the oil vapors containing sulphur compounds, over or into a mass of molten metal capable of combining with the sulphur of said compounds, and also of retaining in solution the combinations so formed; secondly, in passing the oil vapors over or into a mass of melted lead or an alloy of the same, producing lead sulphide, which dissolves in the molten mass; thirdly, in desulphurizing the oil and revivifying the agent without removing the same from its receptacle; fourthly, in revivifying the mass of lead by means of a current of air, and finally in desulphurizing the vapor and simultaneously revivifying the desulphurizing agent.

My invention consists also in certain de tails hereinafter described and pointed out in the claims.

Owing to the temperature of the molten lead, the chemical action is very energetic, the sulphur compounds being reduced by the lead with formation of sulphide of lead, andowing to'the ready solubility of this compound in molten lead it is dissolved as fast as formed and the lead is continually free to act inhampercd by any inert crust.

In order to renew the lead when it becomes saturated or when the amount of sulphur therein becomes so great as to interfere with the successful working of the process, a suitable oxidizing agent. 1lS introduced, which oxidizes the sulphur t'o sulphurous acid gas, partly by direct action, and partly by forming lithargc, which reacting in turn, oxidizes the sulphur with formation of sulphnrous acid gas and reduction of the litharge to metallic lead. The cheapest and most convenient method of thus roasting off the sulphur, is to blow air through the molten mass until sulphurous gas ceases to escape. Any excess of air will form litharge, which will be easily reduced by the first oil vapor of the next run.

I do not contine myself strictly to the use of lead in this process, as alloys of this metal may be used.

In order to render the lead more easily fusi- "ble, other metals, notably arsenic, may be introduced in varying quantities. Zinc, tin, mercury, or antimony or their alloys may also be used, but owing to the simplicity of the action when using lead or an alloy in which lead predominates, it is judged best to use the lead alone or with little foreign alloy.

The drawings hereunto annexed show an apparatus by means of which my process may be carried out, but other forms may be used, and in fact, its structure will depend very largely upon the rest of the refinery.

In carrying out my process, the oil to be desulphurized is distilled in a suitable apparatus, the vapors are conducted by a suitable pipe A, into the desulphurizing chamber 13, where, as heretofore described, the sulphur is retained, and the vapors are allowed to pass on to a condenser through the pipe 0. According to my process, I partiallyfill the receptacle with a mass of molten metal K, and keep the mass in 'a molten state during the entire operation. In practice, I have used a mass of molten lead,but an alloy of that metal will answer, so that my invention comprehends all alloys of lead as well as the pure metal. The oil vapors upon entering the desulphurizing chamber, may be forced down enabling the air conduits to into the molten mass by means of aperforated pipe D leading thereto, or they may be sprayed or impinged upon the surface of the molten metal, the chemical action being the same in both cases. Then it is wished to renew or revivify the lead, the sulphur therein is roasted otf as heretofore described. The air is forced into the mass through the pipe E, and the surplus air carrying gas escapes through 11. The lead is thus ready for use again without having. been removed from the chamber. The vapor and the air outlets are each provided with cocks I, be closed during the desnlphurizing of the vapors, and the vapor conduits to be closed during the desulphurizing of the lead. It is possible, however, to accomplish desulphurization of the vapor and of the lead simultaneously. This I do by introducing into the lead a stream of air so regulated in amount that the sulphur is oxidized as rapidly as it is absorbed by the lead, and passes off with the vapor as sulp'hurous acid gas, which does not react upon the hydrocarbon vapor. The pipe II will of course be closed during this operation.

Having thus described my invention, what I claim is 1. The process herein described for desulphurizing oils which consists in passing the oil vapors through a receptacle containing a mass of melted metal, which will reduce the sulphurous vapors to acommon form of combination, and then combine with the sulphur.

2. The process herein described for desulphurizing oils, which consists in passing the oil vapor into contact with a mass of melted metal, of which lead is the essential element.

3. The process herein described for desulphurizing oils which consists in passing the oil vapor into contact with a mass of melted lead, whereby the sulphide of lead is formed and immediately dissolved, as described.

4. The process herein described for desulphurizing oils, which consists in passing the oil vapors into contact with a mass of melted metal, and subsequently desulphurizing the melted mass by means of an oxidizing agent, substantially as shown and described.

5. The process herein described for desulphurizing oils which consists in passing the oil vapors into contact with a mass of melted lead, and revivifying said lead by means of a current of ail-brought into contact therewith,

substantially as set forth.

FRANCIS J. (IARMAN. Witnesses:

CHAS. E. BRocK,

FLORENCE 'i. BROOKE.

off the sulphurous ICO IIO 

